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Community Member

I lose my multicast packets


I'm working over a multicast network. Now, the network it's up&running, but I want to establish priority to avoid congestion.

My network scheme is like this :

Source Host - router A -(serial) - router B -(serial)-router C-(fast)-Dest Host

In the router B there are other multicast source routers.

I've established a priority for multicast packets over a serial interface (A to B)using acces-list. It goes ok on the source router, but when i try to establish the same priority in the B router over the serial interface (B to C), i don't match any multicast packet in the access-list. So i can't establish the priority over that traffic.

Where are the multicast packets?

How can i establish that priority over the multicast traffic in the router B?


Re: I lose my multicast packets

Depending on the multicast routing protocol you are using and reading through and a few other papers on Cisco's site, I don't think Router B will see those packets as multi-cast unless they are destined for a directly connected network. The QoS precedence bit should still be set and obey'ed by all the routers in the path. You'll probaly have to go over this with your SE or TAC engineer to get a better understanding.

Community Member

Re: I lose my multicast packets

Thanks for your answer

All the things your said are revised. All my multicast traffic is going through all the routers, and now i want to establish a priority QoS.

The multicast is passing though my router, but the access-list is not matching that traffic.

Only If i use that access-list in the interface, the traffic is matched.

Why ?

May it be a IOS bug ? (12.0.7XK1)

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